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Rain sensor failure - how to troubleshoot?

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YOUR RESEARCHRain sensor failure - how to troubleshoot?

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Check fuses, including the unlabeled accessory ones

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Performed · outcome unconfirmed · Original poster

I also checked all the fuses, including the unlabeled accessory ones.

Rain sensor failure - how to troubleshoot?
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Leading evidence: 'Check fuses, including the unlabeled accessory ones' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check fuses, including the unlabeled accessory ones' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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Replace i just got a reply

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Performed · outcome unconfirmed · Original poster

I just got a reply from the PO and he said that when the windshield was replaced, the shop couldn't get an OE applicator (sticker) to attach the sensor to the windshield.

Rain sensor failure - how to troubleshoot?

Check ir emitters

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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

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Suggestion · Original poster

Great idea on using the digital camera to check the IR emitters.

Rain sensor failure - how to troubleshoot?

Check stone

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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

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Suggestion

Check the stone.

Rain sensor failure - how to troubleshoot?

Test output/input

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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

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Suggestion · Original poster

I am assuming that there must be a way to test the output/input.

Rain sensor failure - how to troubleshoot?
Frequently discussed actions (9)

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Check fuses, including the unlabeled accessory ones

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Performed · outcome unconfirmed · Original poster

I also checked all the fuses, including the unlabeled accessory ones.

Rain sensor failure - how to troubleshoot?

Check ir emitters

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Suggestion · Original poster

Great idea on using the digital camera to check the IR emitters.

Rain sensor failure - how to troubleshoot?

Check stone

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Suggestion

Check the stone.

Rain sensor failure - how to troubleshoot?

Replace i just got a reply

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Performed · outcome unconfirmed · Original poster

I just got a reply from the PO and he said that when the windshield was replaced, the shop couldn't get an OE applicator (sticker) to attach the sensor to the windshield.

Rain sensor failure - how to troubleshoot?

Test output/input

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
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Discussions
Read evidence and context
Discussions that contain suggestions
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0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

I am assuming that there must be a way to test the output/input.

Rain sensor failure - how to troubleshoot?

Test relay output/input

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Suggestion · Original poster

Since there are only 3 pins out to the sensor, it seems as though there should be a way of testing the relay output/input.

Rain sensor failure - how to troubleshoot?

Test wiring

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Suggestion · Original poster

Now to start testing the wiring...

Rain sensor failure - how to troubleshoot?

Use digital camera

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Suggestion · Original poster

Great idea on using the digital camera to check the IR emitters.

Rain sensor failure - how to troubleshoot?

Suggestion

So you might turn it on then use a digital camera to see if the IR LEDs are firing.

Rain sensor failure - how to troubleshoot?

Use ir light

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Suggestion

The windshield sensor use IR light.

Rain sensor failure - how to troubleshoot?
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12 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

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POST 1 / ORIGINAL POSTEROriginal post

My rain sensor seems to have failed. It wasn't functioning when I bought the car and I can't seem figure out what the issue is. It is the older version of the relay- the one with the potentiometer on it. The green LED doesn't light up when the wipers are placed in the intermittent setting. I removed the relay, and opened it up and could see nothing visible, including a thorough examination of the circuit board. I dialed the pot up as far and as low as it could go with no change. I also checked all the fuses, including the unlabeled accessory ones. Here are my thoughts: It could be the sensor itself, although I am not sure how it would fail. It could be the wiper stalk that has failed. I could test this by putting in a normal intermittent relay if I had one... Or it could be the relay. Part of the relay has to be working, as if it is completely removed, the wipers won't return to their resting position. Reinstallation fixes this issue. There is a three-prong plug out to the sensor. I am assuming that there must be a way to test the output/input. Thoughts? Any help would be appreciated. I live in Seattle, so you can imagine that I need my intermittent wipers!

POST 3Original post

I would bet it is the relay. I know it is made by a German co. I will see if I have the company name at the house tonight. The windshield sensor use IR light. So you might turn it on then use a digital camera to see if the IR LEDs are firing.

POST 4 / ORIGINAL POSTEROriginal post

Quotes source post: 8179035

Thanks for the tips. I will pull the relay this afternoon and see what I can find out. Since there are only 3 pins out to the sensor, it seems as though there should be a way of testing the relay output/input. I am guessing one is positive, one pin is negative and the last on is the switched return from the sensor. I wish I had a wiring diagram...

POST 5Original post

couldnt find the rain sensor.... maybe this will help.

POST 6 / ORIGINAL POSTEROriginal post

Ferdinand, That is very helpful. Thank you. I just got a reply from the PO and he said that when the windshield was replaced, the shop couldn't get an OE applicator (sticker) to attach the sensor to the windshield. He said it was working before that. If the relay and the wiring is okay then I may have to R/R the sensor with a factory OE sticker. The substitution may be blocking the IR... Cheers, Tom

POST 7Original post

no prob.... gl, and let us know how you make out.

POST 8 / ORIGINAL POSTEROriginal post

Great idea on using the digital camera to check the IR emitters. Here is the result. Clearly the aftermarket applicator is not blocking the IR. Now to start testing the wiring... it is not the stalk, since the sensor is getting switched power. I am going to pull the relay/control unit and see what I can. I have always assumed that the green led that indicates that the system is working is on the inside of the sensor, in the center, behind the mirror. If that is the case, it is not illuminating...

POST 9Original post

Looks like the green LED at the center needs to be ON to show the system is ready according to this http://www.whiteson.org/boxster/mods/rainsensor_tsb.pdf Not much help. Good luck.

POST 10Original post

Check the stone. If it's wet turn the wipers on?? Medieval weather station Stone is wet..... Rains Stone does not move..... Calm Stone moves something..... Lighter wind Stone strongly moves..... Storm Stone is white..... Snow Stone is not to be seen..... Fog or stone pinched

POST 11 / ORIGINAL POSTEROriginal post

Quotes source post: 8180501

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